1. Technical Field
The present invention relates to a system having a drive recorder function and, more particularly, to a drive recorder system adapted to ensure security of drive recorder information recorded on a recording medium.
2. Description of the Related Art
Airplanes are equipped with an apparatus for recording the operation state of the airplane, which is called a flight recorder, and the data regarding the recorded operation state of the airplane is utilized as important evidence when investigating the cause of an airplane accident. In most cases, the investigation of the cause of an automobile traffic accident has hitherto relied on only the statements of individuals involved in and witnesses to the accident, these statements sometimes differing, and to date, verification has taken a lot of time.
To deal with the above problems, rather than relying on witness statements at the time an accident occurs, a “drive recorder” (on-vehicle image recording apparatus) for recording images for several tens of seconds before and after an accident has been conceived. Most manufactured drive recorders are disposed in the vicinity of the rear view mirror and on the front windscreen inside a car. As configurations of such drive recorders, types of drive recorder (integral types) in which parts of a CCD camera and a recorder are integrally configured and types of drive recorder (separation types) in which a CCD camera and a recorder are separated have been put onto the market.
For example, in a system configuration of the related art as shown in FIG. 3, during driving, a subject vehicle and the surrounding state are constantly recorded (using an on-vehicle camera 1 and a GPS receiver 2). When a fixed shock is applied to a vehicle due to an accident (rear-end collision, crash, etc.) or a violent and risky driving operation (sudden braking, sudden steering-wheel operation, etc.), a vehicle sensor 6 (an acceleration sensor, a shock sensor, etc.) detects the shock, and stores, as data, the video (containing the running speed, and in response to the detection, the degree of shock) before and after the detection.
Examples of technologies associated with the related art include a technology in which, as disclosed in Unexamined Patent Application Publication No. US2002/0183905, vehicle data inside a volatile memory is encrypted and is recorded and stored in the non-volatile memory before, upon, and after the collision of a vehicle.
As described above, in the drive recorder system, when considering the use thereof as evidence in proceedings related to an automobile traffic accident, it is necessary that a fixed level of security of stored data (drive recorder information) is ensured. For this reason, as exemplified in FIG. 3, there has been a need to install functions, such as authentication, prevention of tampering, and the like of recorded data via a data encryption process (local encryption from a controller 3 to a removable medium 5).
However, in the related art, when data (encrypted drive recorder information) stored on a removable medium 5 is to be displayed on the screen of a personal computer (PC) 7, specialized analysis software is required. Furthermore, the specialized analysis software is comparatively expensive and has specifications unique to each company. That is, in order to use encrypted drive recorder information, specialized analysis software for each specification of each company needs to be used, presenting a problem in that there is no versatility and also a high cost is incurred.